Under the Kingdom Plantae, which of the following individuals are predominantly aquatic?
- A.Bryophytes
- B.Algae
- C.Pteridophyta
- D.Gymnosperms
Correct answer
Explanation
The correct answer is B, Algae. Algae are the predominantly aquatic members of the Kingdom Plantae. They are simple, chlorophyll-bearing organisms with a thallus body that is not divided into true roots, stems and leaves. Most live in fresh water or the sea, from tiny single cells such as Chlamydomonas to large seaweeds such as kelps, and a few grow on damp soil, rocks or tree bark. They produce a large share of the oxygen on Earth through photosynthesis and form the base of aquatic food chains. Option A is wrong because bryophytes such as mosses and liverworts live on land in damp, shady places; they need water for fertilisation and are called the amphibians of the plant kingdom, but they are not aquatic. Option C is wrong because pteridophytes, such as ferns, are land plants with true roots, stems and leaves and the first vascular tissues. Option D is wrong because gymnosperms, such as pines and cycads, are land plants with naked seeds. Exam tip: algae = aquatic; bryophytes = amphibians of the plant kingdom; pteridophytes = first vascular plants; gymnosperms = naked seeds.
Practice Questions
View allThe fact that the planets move around the Sun, not in circles but in ellipses, was first demonstrated by
- A.Galileo
- B.Martin Luther
- C.Johannes Kepler
- D.Copernicus
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In 1609 Kepler showed that the planets move around the Sun in elliptical orbits, with the Sun at one focus of the ellipse.
Read the full explanation →Which one of the following statements is correct?
- A.Urea is produced in liver.
- B.Urea is produced in blood.
- C.Urea is produced from digestion of starch.
- D.Urea is produced in lung and kidney.
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Liver cells turn the toxic ammonia released from the breakdown of amino acids into urea through the ornithine cycle, also called the urea cycle.
Read the full explanation →Which one of the following is the correct sequence of passage of light in a compound microscope?
- A.Condenser-Objective lens-Eyepiece-Body tube
- B.Objective lens-Condenser-Body tube-Eyepiece
- C.Condenser-Objective lens-Body tube-Eyepiece
- D.Eyepiece-Objective lens-Body tube-Mirror
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Light passes through the condenser to the specimen, is picked up by the objective lens, travels up the body tube and reaches the eye through the eyepiece.
Read the full explanation →Which one of the following statements regarding haemoglobin is correct?
- A.Haemoglobin present in RBC can carry only oxygen but not carbon dioxide.
- B.Haemoglobin of RBC can carry both oxygen and carbon dioxide.
- C.Haemoglobin of RBC can carry only carbon dioxide.
- D.Haemoglobin is only used for blood clotting and not for carrying gases.
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It binds oxygen at its iron-containing haem groups and carries some carbon dioxide on its protein chains. Each haemoglobin molecule has four polypeptide chains and four haem groups, and each haem iron can hold one oxygen molecule, forming oxyhaemoglobin in the lungs.
Read the full explanation →Which one of the following statements regarding histone proteins is correct?
- A.Histones are proteins that are present in mitochondrial membrane.
- B.Histones are proteins that are present in nucleus in association with DNA.
- C.Histones are proteins associated with lipids in the cytosol.
- D.Histones are proteins associated with carbohydrates in the cytosol.
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They are the proteins around which DNA winds to form chromatin in the nucleus of eukaryotic cells. Histones are small basic proteins, rich in the positively charged amino acids lysine and arginine, which attract the negatively charged phosphate groups of DNA.
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